The long-term goal of the candidate in this KO1 application is to launch a focused and sustained program of research in the barriers that inhibit and the potential strategies that facilitate physical activity and improved cardiorespiratory fitness among persons with cardiovascular (CV) risk. Despite the health benefits of physical activity, 51 percent of persons age 65 to 74 engage in no physical activity. A primary national health goal, identified in Healthy People 2010, is to increase the proportion of adults who engage regularly, preferably daily, in moderate physical activity for at least 30 minutes. In no population is this more important than in those with CV risk. A prevalent and significant CV risk factor is impaired fasting glucose (IFG). About 13.6 million Americans have IFG. A significant barrier to physical activity in this population is imposed by osteoarthritis (OA) of the knee, a condition found in at least 2.5 million persons with IFG. Only 15 percent of persons with OA participate in regular physical activity. The underlying pathology can be managed through a program of quadriceps strengthening and graduated walking, yet only half engage in these exercises. A first step in the development of a regular physical activity program of potential benefit to CV disease prevention among older adults may be to address the barrier of OA of the knee. No work has been done in this area. Using a randomized controlled design, we propose to determine whether a self-efficacy based intervention designed to promote adherence to quadriceps strengthening and subsequent walking results in adherence to knee exercise, adoption (6 months) and maintenance (12 months) of regular physical activity (walking), and improvements in cardiorespiratory fitness in a convenience sample of 48 persons age 50 or older with IFG and OA of the knee. Subjects will be randomized to the 24-week intervention or to usual care and assessed at the baseline period, end of the intervention period, and 6 months after the intervention period ends using self-report and electronic pedometer measures of exercise, maximal graded cycle ergometer exercise tests, and an exercise self-efficacy measure. The intervention will incorporate strategies based on self-efficacy theory and consist of six individualized weekly sessions with a physical therapist followed by nine biweekly telephone delivered counseling sessions with a nurse. Data will be analyzed using repeated measures regression techniques.